Association between indoor microbiota, home environment characteristics, and frailty status of elderly residents

Background: The elderly spends a larger proportion of time indoors compared to younger adults. Moreover, the link between frailty status in elderly residents, indoor microbiota exposure, and home environmental factors remain poorly understood. To address this issue, we evaluated the frailty status of elderly individuals aged 60 and older according to the frailty index scale. participants were divided into three groups according to whether the husband and wife exhibited frailty. We collected microbes from the elderly via air precipitation and sequenced the microbes using 16S rRNA and ITS high-throughput sequencing technology. We also investigated the PM1.0, PM2.5, and PM10 concentration, illumination, sound level, wind speed, temperature, relative humidity, living area, and other indicators in their home. Results: : A total of 153 households were analyzed, including 42 households (27.45%) of both healthy spouses, 66 households (43.14%) with frailty in one spouse, and 45 households (29.41%) with both frail spouses.Based on the OTU level, there were significant differences in chao1, reads, and the richness index of the bacterial α diversity index and Simpson index of the fungus a diversity index ( P < 0.05). The Kruskal-wallis test showed that some pathogenic bacteria, including Brevibacterium , Aerococcus , Dietzia , Sanguibacter , and Bacteroides were higher in the group containing both frail spouses compared to the group containing both spouses ( P 1, P < 0.05). A mediating effect model analysis revealed that this process was related to five bacteria genera ( Pseudomonas , Cellulosimicrobium , Chryseomicrobium , Brevibacterium, and Brevibacillus ) and two fungi genera ( Lodderomyces and Trichoderma ). Among these genera, Brevibacillus was a potential protective bacterium for the frailty status of elderly residents, whereas other bacteria were potentially dangerous. Conclusions: : These results illustrated the differential frailty effects of various genera. These findings demonstrate a potential association between the frailty status of elderly residents, indoor microbes, and home environment characteristics.